1. Field of the Invention
This invention relates to a mask, a mask-producing method, and a mask-employing method in a piling process for producing a three-dimensional laminated object.
2. Description of the Related Art
There has recently been developed a technique, a piling process, for producing a three-dimensional laminated object. It is disclosed in Japanese Unexamined Patent Publication (KOKAI) No. 3-183,530 and U.S. Pat. No. 4,247,508. This technique emits energy, such as a laser beam, an ultraviolet ray, to material such as resin-coated sand, liquid resin so as to form a solid layer, thereby piling the plural solid layers in a thickness direction to produce the three-dimensional object.
The present applicant has developed a technique in which a mask covers the resin-coated sand, and in which energy such as a laser beam and an infrared ray is emitted to the resin-coated sand covered with the mask. This technique is advantageous in improving productivity since the laminated product is easily produced corresponding to a designated pattern of the mask. The conventionally developed mask 100, shown in FIG. 17, includes an insular shaped mask-portion 101 having a designated pattern for interrupting energy such as a laser beam, an infrared ray, or an ultraviolet ray, a frame portion 102, and a plurality of supporting arms 103 for holding the mask-portion 101 onto the frame portion 102. The mask 100 is formed by cutting a thin metal plate such as a steel plate, a stainless steel plate, an aluminum plate, by use of a laser beam, thereby having a designated pattern.
For piling the plural solid layers, the aforementioned technique for producing the three-dimensional object requires a plurality of masks. So, this technique requires producing a plurality of masks rapidly and at a low cost.
The conventionally developed mask requires a large output power and a long cutting time, since it is formed by cutting the thickened metal plate such as the steel plate, the stainless steel plate, the aluminum plate, by use of a laser beam. Thus, the conventionally developed mask has a limit in shortening time for producing a mask, and a limit in reducing a mask cost.
Since the conventionally developed mask has a feature that the insular mask-portions 101 is held by the plural supporting arms 103 comprising complicated shapes, it causes an increase of irradiation time and a complicated computer program, thereby inducing disadvantages in shortening time for producing a mask and in reducing a mask cost.